From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-171.mta0.migadu.com (out-171.mta0.migadu.com [91.218.175.171]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id DF9D81E633C for ; Thu, 20 Feb 2025 20:22:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.171 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740082944; cv=none; b=c5gsDE2amkThfFjTFAmlz9uH5E4BWLs8cShq3JaMOFmgUwginX1p97+Kfgtwff44vPoln6GOo7Fk4QR78LK7Ck7s1T71+7oe6zH7RirsRG0uWqHAtXCLkywYxrvs2eBfdg+mBurCakNTzucbS8vxyNPibSZJ/nycReQgxk4I+x4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740082944; c=relaxed/simple; bh=o1DVkTJ3wbmJ5LI04FyppCzlahZhwIHVpaz9/LrVc38=; h=MIME-Version:Date:Content-Type:From:Message-ID:Subject:To:Cc: In-Reply-To:References; b=gVJjmtTfkdvyrldy0H3di47pjv9iHFxS3avnMm355NXYXQaiIAEN86pCdtKWk67GtbphQesMh7OTOvRCYvO/5QhRXepmctpT7Fbiew7Zmd+IbSWoqTj9IFhx+SW54IeKUmDPm3fDrR0P9yVCkrOuwssrEKT9VYkJSW392BVGyrw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=xOwgciiF; arc=none smtp.client-ip=91.218.175.171 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="xOwgciiF" Precedence: bulk X-Mailing-List: cgroups@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1740082939; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CKeHDTPUMbBHbLZBwItw3bMF0jmhlOcG0J5q3cjyQvA=; b=xOwgciiFLizt88nS22ko8ZDXVCXAHLhgF04vRMOM8WVZUfeeB4YbDZ8bQWPY6FsgUR2Q+h IcZkSW2E1niRnVKEhwRyXmIc5LGzW3H/hlcN4huOIKilunufckSOg2VB2b15+OJEF8M+QF LS01nU8bGBJiqIOgKvwFkdfvVwGg/Ws= Date: Thu, 20 Feb 2025 20:22:17 +0000 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: "Yosry Ahmed" Message-ID: <07c9e4355ad4e3982d288306dddf18b391082b14@linux.dev> TLS-Required: No Subject: Re: [PATCH 00/11] cgroup: separate rstat trees To: "JP Kobryn" Cc: "Shakeel Butt" , tj@kernel.org, mhocko@kernel.org, hannes@cmpxchg.org, akpm@linux-foundation.org, linux-mm@kvack.org, cgroups@vger.kernel.org, kernel-team@meta.com In-Reply-To: References: <20250218031448.46951-1-inwardvessel@gmail.com> <158ea157-3411-45e6-bca4-fb70d67fb1c5@gmail.com> X-Migadu-Flow: FLOW_OUT > > Yes, this is true. cgroup_rstat_ops was only added to allow cgroup_b= pf > > to make use of rstat. If the bpf flushing remains tied to > > cgroup_subsys_state::self, then the ops interface and supporting cod= e > > can be removed. Probably stating the obvious but the trade-off would= be > > that if bpf cgroups are in use, they would account for some extra > > overhead while flushing the base stats. Is Google making use of bpf- > > based cgroups? > >=20 >=20 > Ironically I don't know, but I don't expect the BPF flushing to be > expensive enough to affect this. If someone has the use case that loads > enough BPF programs to cause a noticeable impact, we can address it > then. >=20 >=20This series will still be an improvement anyway. I actually just remembered. Using BPF programs to collect stats using rst= at is currently independent of the CGROUP_BPF stuff. So I think this appr= oach breaks that anyway.